Clone states

You can play for free (i.e. without paying a monthly subscription fee), but you will be limited in which skills your character can train. This is referred to as "Alpha".

Paying a monthly subscription to play the game, which allows your character to learn every skill in the game. This is referred to as "Omega".

In-game this system is referred to as Clone States. Characters on Alpha accounts are referred to as "Alpha clones", and characters on Omega accounts are referred to as "Omega clones". If you pay for a subscription (paid for with time cards, monthly payments, PLEX...), your account (and all the characters on that account) receive "Omega" status until your subscription runs out (or you cancel it), at which point they revert back to "Alpha" status. There is no way to tell an Alpha from an Omega clone in-game. The conversion from Alpha to Omega is immediate, while the conversion from Omega to Alpha will always happen when you next log into the game.

If an Omega clone is downgraded to an Alpha clone (because the account's subscription has run out), any skills that character has trained which are not part of the Alpha skill set are locked and become inactive, i.e. they cannot be used, but the invested skill points will not be lost. Any items or ships which require the locked skill become inactive and cannot be used, and the skill training queue will be paused (but can be resumed by logging into the game). If the account's subscription is renewed, then the character is automatically upgraded back to an Omega clone and can once again use all the skills they have previously trained.

Alpha or Omega status is tied to your game account. If you have multiple accounts, then you can choose to pay for a subscription for some, all or none of them, and each account (and the characters on that account) will have the corresponding Alpha or Omega state.

Alpha clones are welcome to join EVE University, however, there are some limitations on which titles Alpha clones may receive.

Gameplay

While they are well suited for getting introduced to EVE Online, Alpha characters should be seen more as an "indefinite trial" rather than as a "free-to-play" option.

Combat

Alpha characters are perfectly viable in low-level PvP and PvE, and in support roles in larger-scale PvP (such as EWAR or tackle for a fleet). However, their performance will not be on par with Omega characters once the latter has trained the skills to start using Tech 2 modules and ships.

Industry

Alpha characters can mine (ore or gas) in a Venture (but not use more advanced mining ships), and can perform basic (only Tech 1, no invention) manufacturing. While they will not be as efficient as an Omega character (who have access to more advanced ships and skills which improve mining and manufacturing efficiency, and are not subject to the addition 2% tax levied on Alpha characters), they can nonetheless participate in basic industry. They can salvage wrecks, but they cannot, however, do Planetary Interaction.

Alpha characters can trade, but they will pay higher taxes on their transactions and have fewer options at their disposal (e.g. they can only sell items located within 5 jumps, whereas an Omega character has the option to train skills allowing them to sell items anywhere in the current region). Alphas can have 1 active contract at a time (i.e. they can create 1 contract, but have to wait for it to be fulfilled before creating another), but they can accept contracts.

Basic hauling is an option for Alpha characters as they have access to Tech 1 industrial ships.

Exploration

Choice of race

Alpha clones can train into any race's ship or weapon skills; they are not limited to training their own race's skills. In fact, Alpha clones of all races can train into the same Alpha skill set. However, the Alpha's starting racial skills count toward the free training skill limit while in Alpha clone state.

Omega clones

Omega clones may use any skill, ship and item in the game. Additionally, you may log into the game with more than one account at a time (multiboxing), but only as long as all the accounts being logged in have Omega status.